Alfa Romeo Giulia Forum banner
1 - 20 of 81 Posts

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #1 ·
I've mounted Michelin Pilot Super Sport (255/35x19) on AR 5-Hole (dark) Teledial wheels and installed them on all four corners of my Giulia Ti. These are the rear wheels from the staggered wheel set that's only available after you've already selected the Ti 19 Inch Performance Package. The staggered wheel package uses 19x8 wheels on front and 19x9 wheels on rear.

I ordered them individually to get four 19x9 wheels.

Parts List (USA numbers):
  • 6FM59U5GAA - WHEEL (Dark 5-Hole)
  • 68336101AA - SENSOR (TPMS valve - Tire Pressure Monitoring System)
  • 68311633AA - CAP (black center cap from Quadrifoglio)
  • 6509906AA - BOLT (guide pin and rotor to hub lock, REAR)

The entire package including tires cost me about $3,500. My dealer claims to have given me a special price, so I won't quote any prices. The guide pins cost me $1.10 each and will be discussed later. The TPMS valves did not include nuts which I was able to purchase from my tire shop.

It took me quite a while to get the part numbers because AR is still setting up the parts inventory system. Then I ran into a few snags which took time to sort out. But now it all seems to be working well.


Side View
Because we ordered the Lusso interior, we were locked into the 18x8 10-Spoke Aluminum Wheel set with 225/45x18 Pirelli tires.
Note the chrome trim around the windows.
Yes, that's my red 4C and brown truck in the background. The outhouse is for the construction crew building our new garage. Maybe we'll be able to park our Alfas indoor by Christmas.



19x9 Dark 5-Hole 'Teledial' Wheels with 255/35x19 MPSS tires.



Front Quarter





Rear Quarter




More pictures to follow in the next post.
 

·
Registered
Joined
·
296 Posts
Looks great!!!
So how do you like your 4C?
Quick review?
I am wondering if one should be in my future.
Would love to see a 4C Quadrifoglio version with a bit more motor :)
 
  • Like
Reactions: Racer Z

·
Registered
Joined
·
1,964 Posts
Z, looks great.
Just today, I was at the Studio to pick up a 91 164L that was traded on a new Giulia.
I asked the Parts Dept. dude to price out a 19" black wheel set for me, so I could have another set for our (ordered) MY2018 Ti Lusso.
Please post A-B observations when you get a chance.
Cheers!
 
  • Like
Reactions: Racer Z

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #4 · (Edited)
Looks great!!!
So how do you like your 4C?
Quick review?
I am wondering if one should be in my future.
Would love to see a 4C Quadrifoglio version with a bit more motor :)
I have 27,000 miles on her. I'm still on my test drive :grin2:
Oh I just love her to death. She's my daily driver. My wife and I drove her to Seattle and back, 4,000 miles in three weeks. Backroads north through the mountains, coast route south back to Los Angeles. Perfect car on those perfect roads. I actually prefer driving my 4C over the Giulia. She drives like she looks.

There's enough performance parts out now that pumping the motor is easy. For a serious track car, suspension needs to be worked on first. Don't count on AR doing anything special with 4C. I think 2018 will be the last year on the 4C.


Z, looks great.
Just today, I was at the Studio to pick up a 91 164L that was traded on a new Giulia.
I asked the Parts Dept. dude to price out a 19" black wheel set for me, so I could have another set for our (ordered) MY2018 Ti Lusso.
Please post A-B observations when you get a chance.
Cheers!
Will do. I had to stop my documentation early. I do have a life outside these forums. My father and I went on a bicycle ride along the coast. 17 miles. He's 79 years and kicked my @$$.
 

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #5 ·
Jack Points

Jacking the car is easy. In the service repair manual I bought, it says there are only four points you can safely lift the from. When you look under the car, you will see a knob. That is the only jack point, according to Alfa.

I used my lowboy racing jack. My wife had flattened one tire and the jack fit fine. A regular floor jack probably would not have gotten under the flat corner.

The lugs take a 17mm socket. My dealer tells me these are the same lugs used on the 4C. The holes in the wheels have enough clearance that a reinforced impact socket will fit. I used a breaker bar.




 

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #6 · (Edited)
Guide Pins, Hubs & Rotors

Removing the front wheel revealed a guide pin. But, the wheel does not have a matching hole, just large cavities. I had a good idea where this was going. And mounting the new 'rear' wheels on the front proved my educated guess to be true. The rear wheel would not sit flush on the front hub.







The rear hubs have a flush pin, so I ordered two rear pins and installed them on the front. The pins were only $1.10 each, but I had to wait almost a week. I did drive for a week with my new wheels and no front pins. It's not really a big deal, but for a buck each, I bought the rear pins.




The pins do more than prevent placing the wrong wheel from being placed on the wrong hub. They lock the rotor to the hub. This is more for ease of mounting the wheel. The rotor will spin on the hub very easy.






I'd like to point out the flange on the hubs. These are concentric mounting hubs. There's a matching cylinder in the wheel to fit this flange. It's there to center the wheel on the hub. The lugs are there to hold the wheel to the hub. This concentric flange also adds a lot of strength so the lugs don't have to take all the load.

If you buy wheel spacers, make sure they are hub-concentric spacers. Don't let anybody tell you it doesn't matter. It matters.

I'm not using wheel spacers. As you have seen and will see more later, these wheels fill the wells and are very close to rubbing.
 

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #7 ·
Tires

I chose Michelin Pilot Super Sport tires in the OEM size for these wheels. 255/35x19 The tire has a 300 treadwear rating. I am guessing I'll get 30,000 miles out of these tires. But, I'm just tossing out numbers. I put these on my 4C after the Pirelli P-Zero wore out, 220 treadwear and 20,000 miles. I like them on my canyon carver and didn't give it a second thought for the Giulia.

The P-Zero is a small tire for it's rated size.
The MPSS is a large tire for it's rated size.

I still have less than 100 miles on these with the Giulia. I'm still breaking them in and letting the bead lube dry. But so far they are great.

The Ti came with colored center caps. I bought black caps from the Quad. I can swap them out anytime if I want. So far, I really like the dark look.



A lot wider.



A little shorter.



 

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #8 ·
Finally, I had the new wheels mounted, air pressure adjusted and carefully test drove the car. The front tires are close to rubbing the fenders and I didn't want to damage anything. I've seen the results of others who were, hmm, careless.

I found an empty parking lot and did a few full lock circles. Full left, no rubbing. Full right and then both directions while in reverse with no rubbing. What I did notice is the Ackerman Angle was more noticeable. The tires skipped a bit more, but only at full steering lock.

In normal driving at normal speed, it's all good.

I drove around looking for a special place and eventually found what I wanted. A way to stress the suspension while parked.




Right Front. Amount of compression unknown.



Left Rear, compressed.



Left Front in droop.



Right Rear in droop.
 

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #9 ·
Follow-up Report

I had the car aligned. The non-adjustable front camber/caster was spot on. The rear adjustable camber was spot on. Both front and rear toe was off, not much, but got reset. To drive the car, I can't tell the difference, but I feel better.

I'm using 35/35 psi in the tires.

She drives nice. I haven't pushed her yet. I waiting for the bead lube to dry. I was concerned that the steering would get heavy, but it seems fine. With the exception of one time, I haven't heard any rubbing or felt anything I should not feel.

There was one time that I thought a front tire had rubbed. My father and I had gone to lunch. I was turning and hit a minor bump, I heard what sounded like one of the front wheels rubbing. It did not feel like a rub though. In my very thorough inspection later, I could not find any signs of a rub.

I have just under 100 miles now. I removed both front wheels to install the guide pins and inspected for signs of rubbing and other unwanted things. No signs of anything ugly.

ATM, I think all is good. Time will tell though.
 

·
Registered
2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
Joined
·
7,738 Posts
I had the car aligned. The non-adjustable front camber/caster was spot on. The rear adjustable camber was spot on. Both front and rear toe was off, not much, but got reset. To drive the car, I can't tell the difference, but I feel better.

I'm using 35/35 psi in the tires.

She drives nice. I haven't pushed her yet. I waiting for the bead lube to dry. I was concerned that the steering would get heavy, but it seems fine. With the exception of one time, I haven't heard any rubbing or felt anything I should not feel.

There was one time that I thought a front tire had rubbed. My father and I had gone to lunch. I was turning and hit a minor bump, I heard what sounded like one of the front wheels rubbing. It did not feel like a rub though. In my very thorough inspection later, I could not find any signs of a rub.

I have just under 100 miles now. I removed both front wheels to install the guide pins and inspected for signs of rubbing and other unwanted things. No signs of anything ugly.

ATM, I think all is good. Time will tell though.
That sounds like too much pressure for such a wide tire. Note that Michelin specifies that increase pressure is appropriate if your average speed is expected to be over 100MPH but that is not much of an issue for legal road driving. On the track the situation may be completely different (depends on the track).

Mounting the tires on 8.5" rims (i.e. Quadrifoglio front rims) would squeeze the sidewall bulge of the tire down to about the width of a 245 mounted on a 9" rim. That might not do handling any good though. Is clearance good on the inside of the wheels?

Have you weighed the assembly? Have you weighed your 18" wheels for comparison?

Please keep us posted on the rubbing issue (or non-issue?). I wonder if the steering is turned and the suspension compressed if the stock wheels will rub the wheel arch.

As soft as the steering is on this car is, I would think a little more resistance to turning would be welcome.

I would think that the pins could be tossed is if a wheel stud kit is installed.
 

·
Vendor
Joined
·
619 Posts
Looks great, nice OEM+ improvement!
 
  • Like
Reactions: Racer Z

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #15 ·
That sounds like too much pressure for such a wide tire. Note that Michelin specifies that increase pressure is appropriate if your average speed is expected to be over 100MPH but that is not much of an issue for legal road driving. On the track the situation may be completely different (depends on the track).
I'm starting with 35/35 because my service mgr recommended that. There was a car in the lot with this staggered wheel set and it calls for 33 psi on these tires.
8 inch front: 35 psi (225/40x19)
9 inch rear: 33 psi (255/35x19)
I'll probably lower the pressure to 33/33.

Forty years ago I worked at a tire shop. We had more road hazard failures with Michelin than any other brand. We always suspected this was because Michelin recommended a lot more air pressure than the other brands.

Mounting the tires on 8.5" rims (i.e. Quadrifoglio front rims) would squeeze the sidewall bulge of the tire down to about the width of a 245 mounted on a 9" rim. That might not do handling any good though. Is clearance good on the inside of the wheels?
If memory serves, the Quad has 8.5/10 inch wheels. They don't stuff a 255 on that skinny front rim.
Inside clearance is tight. It is a tight fit everywhere. Hard cornering will flex things and might rub somewhere. Maybe.
I definitely would not use a larger tire than this.

Have you weighed the assembly? Have you weighed your 18" wheels for comparison?
No, I have not weighed anything yet.

Please keep us posted on the rubbing issue (or non-issue?). I wonder if the steering is turned and the suspension compressed if the stock wheels will rub the wheel arch.

As soft as the steering is on this car is, I would think a little more resistance to turning would be welcome.
On my Ti Q2, dynamic firms up the steering feel. It is not too firm. It sort of feels a little firmer with these tires, but not too much. After a few miles it seemed normal and I could no longer tell and I got to wondering if it only felt firmer because I was expecting it to feel firmer.

I would think that the pins could be tossed is if a wheel stud kit is installed.
You could. Unless the spacer has the appropriate recess for the pin, you'd have to loose the pin.



Another issue that might show itself is corner wear. These wide front tires might get bad edge wear. That's a long term test. The nice thing is that I can rotate my tires :)
 

·
Registered
Joined
·
55 Posts
Racer Z, you are a hero. Very subscribed to this thread and what you find out along the line.
 
  • Like
Reactions: Racer Z

·
Registered
Joined
·
2,988 Posts
Discussion Starter · #17 ·
Any plans to experiment with the tire pressure at all?
Yes, I'm going to drop them to 33/33. If she drives OK and if I don't have unusual tread wear, that's where she'll stay. Tread wear will take some time to show up.

The good news is that we are leaving for the east coast soon. We're going to log 8,000 miles real quick. That should show off the tread wear.
 

·
Registered
2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
Joined
·
7,738 Posts
I'm starting with 35/35 because my service mgr recommended that. There was a car in the lot with this staggered wheel set and it calls for 33 psi on these tires.
8 inch front: 35 psi (225/40x19)
9 inch rear: 33 psi (255/35x19)
I'll probably lower the pressure to 33/33.
Ideal psi is not trivial to determine, particularly for driving on the road. I think you want to decrease pressure pretty close to proportionally to the width increase for best contact patch but that much pressure change may make the wheel more susceptible to damage from rocks and similar narrow road hazards.

Forty years ago I worked at a tire shop. We had more road hazard failures with Michelin than any other brand. We always suspected this was because Michelin recommended a lot more air pressure than the other brands.
45 years ago my Dad's Fiat 124 Coupe (which had Michelin tires) had a blow out on the freeway for no obvious reason. The sidewall was ripped and today I suspect that the tire simply failed (there were 5 people in the car at the time). Hopefully all of that is a thing of the past.

OTOH: I do not run Michelin tires on my bicycle; I had way too many problems with them. I run the Italian brand (made in Thailand though) Vitorria. They are nearly indestructible. Vittoria doesn't make car tires though, and scaled up to car tire size you might not like the price ($55 for a 23mm wide tire). The latest versions are carbon nano tube re-enforced.

If memory serves, the Quad has 8.5/10 inch wheels. They don't stuff a 255 on that skinny front rim.
Inside clearance is tight. It is a tight fit everywhere. Hard cornering will flex things and might rub somewhere. Maybe.
I definitely would not use a larger tire than this.
QV comes with 245s in the front. This is part of the cause of my concern about rubbing with 255s on the front. Tirerack says that 255s can fit on a 8.5 inch rim, but that is not the same as saying that it will handle well.

I wonder if the folks at the Signal Hill Madness Autoworks (they are maybe 20 miles from Venice?) have the tools and training to do a full clearance check on your car? I might be convinced to send you a check to cover some of the cost if necessary, since I would rather not spend $3000-4000 on a "problem" summer setup. They probably have a scale with the right range for tires too. PM me if you want to work something out.

No, I have not weighed anything yet.
Please see if you can before your road trip. Otherwise tire wear will throw off the rim weight estimation.

O.Z. makes light weight rims for Giulia. I have no idea if those rims are any good strength and rigidity wise. They are slightly less expensive than the OEM 19" 5 hole rims.
 

·
Registered
Joined
·
658 Posts
That sounds like too much pressure for such a wide tire.
What would you be running in this type of tire?
Alfa Romeo is recommending 34psi for this size in run flat. Do you think it should be different for the MPS 4's?
 

·
Registered
2018 Q4 with Fiamenghi Ti exhaust, Race Mod, and Tecnico wheels.
Joined
·
7,738 Posts
What would you be running in this type of tire?
Alfa Romeo is recommending 34psi for this size in run flat. Do you think it should be different for the MPS 4's?
I am certainly not an expert, but for best contact patch size/shape I think the pressure should be between 30 and 33PSI for 255mm tires on a Q2 or Q4 Giulia with no passengers. I would use 32PSI as a starting point. Lower for acceleration performance, higher for cornering performance. Instrumented tests on a track would be the best approach. A far IR camera can be used to visualize the width of the contact patch by looking at the temperature of the tread. To get it dialed in to a particular model of tire definitely requires trial and error.

However, with such low profile tires there is always the risk of a "pinch flat" especially on the highway. A pinch flat happens when the tire is compressed enough to break the bead seal or crush/damage the sidewall against the rim and/or bend/break the rim. The risk of pinch flatting is reduced by running a higher pressure. If the pressure is too high though, you would have been better off with narrower tires.

On road the tire pressure varies a lot with driving and road condition due to tire temperature and elevation (e.g. my weekly "run" starts at sea level and peaks at 9600 feet, causing over 3PSI in pressure change), so for non-track use it may be pretty much pointless to try to dial it in to a great deal of accuracy.
 
1 - 20 of 81 Posts
Top